Insulating Heat Ducts In Attic

First consider the duct location.

Insulating heat ducts in attic.

Replacing your ducts is another option when you ve got old uninsulated ones. Of course you might also consider replacing your old ducts. So logically the ducts deserve more not less insulation. Out with the old in with the new.

But whether you hire us or somebody else be sure your contractor follows these steps. Acute temperatures in these areas contribute to thermal loss in metal ductwork. Because the simplest and cheapest way to insulate an attic is to add material to the floor. Plan to pull up the flooring and layer new insulation on top of the old.

When these ducts are exposed to exterior air the plastic jacket never gets cold enough to permit condensation because the hot attic air keeps the plastic jacket warm. Use a paintbrush to apply duct mastic to the joints where an elbow. Other times insulation may be on the outside. Our team follows a rigorous process for replacing ductwork.

Sometimes the insulation is inside the ductwork. When hvac ducts are installed in a vented attic in a dry climate bury the ducts in attic insulation to protect them from temperature extremes in the unconditioned attic space. Use the type of metallic foil duct tape recommended by the insulation manufacturer to seal and hold the insulation in place. But the air in the ducts is facing a delta t of maybe 100 f or 120 f a greater delta t.

A metal duct conveying cool conditioned air through a broiling attic in summer or warm air through a chilly crawl. Flexible ductwork comes with different insulation r values. Press a continuous strip of foil tape to all longitudinal seams along straight runs of duct. After all most new homes have r 49 insulation on the attic floor holladay continues.

Make sure the foil surface of the insulation is free of dust before applying the tape. But if the floor is covered in plywood you can t stuff enough insulation beneath it to do the job sufficiently not even in warm climates. When insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value. Because the moving air is in the ductwork for only a short period of time it does not need the insulation r value the attic floor requires.

The greater the temperature extreme between the air inside the duct and the air surrounding the ductwork the greater your need for duct insulation. Check the speed of the blower motor on the furnace. If necessary switch the wires to reduce the blower to its lowest. Most attic ducts are insulated flex ducts that is flex ducts with r 6 or r 8 fiberglass insulation along with an exterior polyethylene jacket.

When the attic is 20 f that insulation is addressing a delta t of 50 f.